Hello,
You can run pre and post commands by means of a batch file in order to start and stop the services. For more information on that, refer to the following technotes:
Title: How to execute batch files and executables (pre- and post- job commands) before and after a backup via the Backup Exec GUI
http://support.veritas.com/docs/240664
Also check the following technote:
Title: Available parameters for pre- and post job commands in Backup Exec 9.x and 10.0
http://support.veritas.com/docs/259941
Hope this helps. In case you have some more questions regarding this, do write back to the forum. However if do not receive your update within two business days, this post would be marked assumed answered and would be moved to answered questions pool.
Regards.